Hydrofoil boat



NOV. 24, 1931. 5,5" BREESE 1,833,481

HYDROFOIL BOAT Original Filed May 6, 1929 INVENTOR wimw ATTORNEYS Patented Nov. 24, 1931 PATENT OFF ICE SYDNEY S. BREESE, OF WOODBURY, NEW YORK HYDROFOIL BOAT Application filed May 6, 1929, Serial No. 360,876. Renewed April 21, 1931.

This invention relates to boats.

More particularly stated, the invention relates to boats of the submerged hydrofoil type, equipped with hydrofoils and so constructed that under running conditions the boat proper or the hull will be supported on the hydrofoils free of the water.

This type of water craft has been variously designated as a hydrodrome, hydroplane boat, hydrovane, etc., and such a structure is shown in Patent No. 1,410,877 granted March 28, 1922 to Bell, Baldwin and Breese.

The most difficult problem to be solved in the design of a boat of the character specified, resides in the steering or turning of such a boat at the high speeds at which the craft can be driven. Great power and leverage are required, as illustrated for instance by the structure disclosed in Patent No. 1,112,405 to Forlanini.

As a matter of fact, a rudder of the conventional type, even when given excessive area and placed in a position to exert great leverage about the pivotal point of the boat, has been found to be unsatisfactory. Furthermore, such a construction presents a great handicap to the commercial development and adoption of this type of boat.

Consideration of the conditions which must obtain to accomplish sharp and accurately controlled changes in direction at high speed, discloses the reasons for this failure of the conventional form of rudder. In the first place, owing to the height of the center of gravity above the plane of the supporting hydrofoils, any change in direction will be accompanied by a tendency of the boat to tilt or list outwardly and to lose its equilibrium and capsize. Secondly, such a change in the direction of the boat will result in a tendency of the boat to slip or skid sideways.

An obvious and simple method of preventing the undesirable results or' tendencies above mentioned, is to slow down the boat very considerably when a turn is made. This, of course, results in a loss of speed. Another method is to exert some force on the craft that will counteract the tendencies mentioned and will cause the boat to bank or incline in the direction toward which it is turning. This inclination is exactly as necessary as and is strictly analagous to the banking of an aeroplane when turning.

When a boat is turned at a given speed, the sharper the turn, the greater is the centrifugal force to be overcome. From this it follows that a greater power must be exerted on the craft to overcome the centrifugal force or, in other words, the more the boat must be inclined in the direction of the turn.

This invention has for its salient object to provide a simple and efficient steering and controlling mechanism for a boat of the character specified, so constructed and arranged that side slip, outward listing and overturning will be effectively prevented.

Another object of the invention is to provide simple, practical and efficient steering and control mechanism for a hydrofoil boat, so constructed'and arranged that turns may be made at sharp angles while the boat is being operated at high speeds without danger of side sli 3 or capsizing.

Another ob ect of the invention is to provide a hydrofoil boat with propelling and steering mechanism so constructed and arranged that the boat will incline when turning toward the center about which the turn is being made and the inclination will bear a definite ratio to the speed of operation of the boat.

Further objects of the invention will appear from the following specification taken in connection with the drawings, which form a part of this application, and in which Fig. 1 is an elevational view, somewhat diagrammatic, illustrating a hydrofoil boat with steering mechanism constructed in accordance with the invention;

Fig. 2 is a top plan view of the construction shown in Fig. 1; V

Fig. 3 is a rear end elevation of the structure shown in Fig. 1;

Fig. 4 is a top plan view, partly broken away, showing a slightly different form of construction embodying the invention;

Fig. 5 is a side elevation illustrating a further modification of the invention; and Fig. '6 is an end elevation of the rear end the bow.

portion of a boat illustrating a further embodiment of the invention. 7

The invention briefly described consists of a hydrofoil boat comprising a hull having a plurality of sets of hydrofoils suitably carried thereby and adapted to support the boat when the craft is being propelled at a sufficient rate of speed, and propelling mechanism extendin downwardly or disposed below the hydrofoils, and means for swinging the propelling mechanism angularly relative to the longitudinal of the boat.

When the propeller is so mounted and a turn is to be made, the axis of the propeller is angularly adjusted andthe angular thrust of the propeller counteracts the centrifugal force acting to overturn the boat. 4

Further details of the invention will appearlfrom the following description.

r In the form of the invention illustrated. in Figi- 1, there is shown a boat 10 whichmay be of any suitable size andshape. Twosets of hydrofoil's, A and B, are secured tothe hull. of the boat and extend downwardly therefrom.- -Set Av comprises hydrofo1l blades of suitableconstruction, which are secured to braces or struts 16 and .17..

Set B ofhydrofoils is disposed at the sternof the boat and consists oftwo sections, C and- D, disposed laterally of the body of the boat and each comprising hydrofoil blades 20 carried by curved struts: or braces 21. The two sections C and D are connected by a cross rod 22 which is mounted in lugs 23 extending rearwardly from the stern of the boat. It will be understood that other forms of hydrofoil. structures may be employed and further details of the structure of the hydrofoil sets is deemed unnecessary since the structure is similar to that illustrated in: Patent No. 1,112,405 above referred to. a

In additionto the two sets of hydrofoils, a fin 25' is secured to the bottom of the boat and extends downwardly therefrom adjacent It will be obvious that when a boat of the type illustrated in Figs. .1 and 2 is operating at high speeds and is supported on the hydrofoils-,the center of gravity of the boat will be located a considerable distance above the surface of the water. This condition seriously complicates the turning of the boat and gives rise to the tendencies mentioned at the outset of the specification.

In order to counteract the centrifugal force tending't'o overturn the boatwhen it is turned at high speed at a sharp angle, the propelling mechanism is mounted in such a' way that the line of thrust of the" propeller is altered when the boat is turned, thereby causing the thrust to exert a' force outwardly or away from the center about which the boat is turning;

1 Since the propeller :is located below the plane offsupport ofIthe boat, the thrust which In the form of the invention illustrated in Figs. 1, 2 and 3, a motor M is mounted in the boat and has connected thereto a shaft which extends downwardly therefrom in a casing 30. The shaftin the casing 30 is connected at its lower end by bevel gears or in any other suitable manner to a propeller shaft which is disposed at right angles thereto and has mounted at the rear end thereof a propeller 31. The casingSO is pivotally mounted and is adapted tobe turned by tiller ropes connected. to tiller 32. Attention is called to the fact that the propeller 31 is located below the vertical center of lift of the hydrofoil blades andthus the propeller will be disposed in the water at all speedswhen the boat is sup ported on the hydrofoils. The vertical center of lift at any given speed may be defined for the purpose of this specification as the point about which the lifting forces exerted by the hydrofoiis are in balance.

YVhen' a turn is to be 1nade,tl1e casing 30 is swung in one direction or the other by the tiller, thus altering the angle of thrust of the propeller and causingthe thrust to exert aforce outwardly from the center about whichQthe boat is turned. Furthermore, as above stated, since the force is exerted below theplane of support or below the vertical center of lift, it will tend to throw the center of ravity of the body which is disposed above theplane of support in a direction opposite tothe thrust or inwardly toward the center about which the turn is being made. Inthis manner the boat is caused to turn and bank simultaneously, thus counteracting skidding-and preventing the boat from cap: sizing.

In theform of the invention illustrated in Fig. 4, the construction is similar to that shown in Figs. 1 and 2 but differs therefrom in that the motor M is mounted to turn with the casing 30 which extends downwardly propeller 47 is connected to the rear end of the shaft 43. i

In Fig. 6 the motor M drives a shaft 50 which is connected by bevel gears 51 and 52 to a vertical shaft 53 carried by a casing 54. A propeller 55 is mounted on a shaft 56 connected by gears 57 and 58 to the shaft 53. The shaft 56 and gears 57 and 58 are housed in a casing 59 which is connected to the lower end of the casing 54. The casing 54 is rotatably mounted and is provided with a handle 60 by means of which it can be angularly adjusted.

It will be obvious that the angular adjustment of the line of thrust will be obtained by the structures shown in Figs. 4, 5 and 6, in the same manner as was described in connection with the embodiment of the invention shown in Figs. 1 to 3. In all of the forms of the invention, the same results are accomplished, and it will be obvious that a hydrofoil boat, provided with propelling and steering mechanism constructed as described can be turned at a sharp angle when running at high speeds without danger of side slip or overturning.

Although certain specific embodiments of the invention have been particularly shown and described, it will be understood that the invention is capable of modification and that changes in the construction and in the arrangement of the various cooperating parts may be made without departing from the spirit or scope of the invention, as expressed in the following claims.

What I claim is:

1. A hydrofoil boat comprising a hull, a lurality of sets of hydrofoils carried therey, propelling mechanism extending downwardly below the vertical center of lift of said hydrofoils, and means for swinging said mechanism angularly relative to the longitudinal axis of the boat, whereby the boat may be turned, and banked.

2. A hydrofoil boat comprising a hull, a plurality of sets of hydrofoils carried thereby, a propeller disposed lower than the vertical center of lift of hydrofoils, means for driving said propeller, and means for tilting said propeller angularly relative to the longitudinal axis of the boat, whereby the boat may be turned, and banked.

3. A hydrofoil boat comprising a hull, a plurality of sets of hydrofoils carried therea propeller disposed lower than the vertical center of left of hydrofoils, means for driving said propeller, and means for tilting I the axis of rotation of said pro eller angularly relative to the longitudina axis of the boat, whereby the boat may be turned, and banked.

4. A hydrofoil boat comprising a hull, a plurality of sets of hydrofoils carried thereby, a propeller disposed lower than the vertical center of lift of hydrofoils, means for anked.

SYDNEY S. BREESE. 

